This invention relates to treated calcium/oxyanion-containing particles and their use in medical diagnostic imaging techniques, such as magnetic resonance imaging ("MRI"), magnetic resonance spectroscopy ("MRS"), magnetic resonance spectroscopy imaging ("MRSI"), X-ray, and ultrasound. The present invention also includes novel apatite and apatite precursor particles, manufacturing methods, and coating compositions which prevent particle aggregation, improve particle stability, and permit functionalization of the particle surface.
The use of contrast agents in diagnostic medicine is rapidly growing. In X-ray diagnostics, for example, increased contrast of internal organs, such as the kidneys, the urinary tract, the digestive tract, the vascular system of the heart (angiography), etc., is obtained by administering a contrast agent which is substantially radiopaque. In conventional proton MRI diagnostics, increased contrast of internal organs and tissues may be obtained by administering compositions containing paramagnetic metal species which increase the relaxivity of surrounding protons. In ultrasound diagnostics, improved contrast is obtained by administering compositions having acoustic impedances different than that of blood and other tissues.
Often it is desirable to image a specific organ or tissue. Effective organ- or tissue-specific contrast agents accumulate in the organ or tissue of interest.
From the foregoing, it would be an important advancement in the art to provide organ specific medical diagnostic imaging agents. Specifically, it would be an improvement in the art to provide organ specific MRI, X-ray, and ultrasound contrast agents.
Such medical diagnostic imaging agents are disclosed and claimed herein.